Method for preparing spherical 3-nitro-1, 2, 4-triazole-5-ketone crystal

The invention provides a method for preparing a spherical 3-nitro-1, 2, 4-triazole-5-ketone crystal, and relates to the technical field of energetic crystal materials. The preparation method comprises the following steps: dissolving 3-nitro-1, 2, 4-triazole-5-ketone in a solvent to obtain an explosive solution; respectively introducing a non-solvent and the explosive solution into a microreactor for mixing, primary crystallization and crystallization to obtain the spherical 3-nitro-1, 2, 4-triazole-5-ketone crystal, the solvent comprises one or more of N-methyl pyrrolidone, acetone and gamma-butyrolactone, and the non-solvent comprises 1, 2-dichloroethane and/or trichloromethane; the microreactor comprises a valve type mixer and a labyrinth reactor which are connected in sequence, the mixing and the primary crystallization are carried out in the valve type mixer, and the crystallization is carried out in the labyrinth reactor. The NTO crystal prepared on the basis of the micro-reaction technology is high in s